Coating or sizing treatment of yarns



Patented Apr. 15, 1947 COATING on SIZING TREATMENT OF YARNS Herbert Freund, West New York, N. 3.

No Drawing. Application .fune 3, 1943, Serial No. 489,492

1 Claim. i

This invention relates to a coating or sizing treatment of yarns. The invention is particularly concerned with, but is not limited to a treatment of artificial yarns originating from cellulose preparatory to the flat-knitting thereof into a sheer, full-fashioned hosiery fabric.

Yarn which is used for the knitting of sheer, full-fashioned hosiery is subjected to a considerable amount of rough treatment before, during and after the knitting operation.

Natural silk in the gum is capable of withstanding this rough treatment dueto the presence of a natural protective coating of sericin, binding the silk filaments firmly into a solid thread. n the other hand, ingrain silk which has no such coating was found unsuitable for hosiery knitting due to an excessive proportion of pulled threads.

Synthetic yarns presented the same problem.

In order to adapt such yarns to flat-knitting and similar operations requiring rough treatment it was found necessary to size these yarns, i. e., to apply to them an adhesive coating protecting the filaments during the knitting operation and in the course of the subsequent handling of the fabric.

It is well known that yarns made of cellulose base require no size for knitting underwear fabrics on tricot or circular knitting machines, these yarns only being oiled. However, for full fashioned hosiery knitting, a carefully balanced sizing is essential.

Protein sizes which were recently developed for knitting yarns made from synthetic polymers, such as Nylon," are not suitable for yarns made from cellulosic materials.

The application of size to knitting yarns made from a cellulose base is a relatively new and undeveloped art. Since yarns in a wet condition are very sensitive to stretching when treated with sizing containing a relatively high amount of water, it has been suggested to use so-called "dry sizes containing waxes, fats or oils of certain kinds dissolved in inflammable solvents.

Such sizes present a continuous fire hazard in knitting mills and are very expensive.

One of the principal objects of the present invention is the provision of a size for yarns made from a cellulose base which is satisfactory for suitable for other purposes and. in fact, for various synthetic yarns. In rder to obtain this object the sizing mus adhere well and bind the filaments together during twisting, twist setting and subsequent operations. It must not gum knitting needles and sinkers as otherwise it will prevent the yarn from running well on the knitting machines. The sized yarn must not stick to the guides and snappers of theknitting machine and cause corrosion and abrasion of the contacted machine parts, the size must notaccumulate on needles and sinkers. as otherwise holes and runs in the fabric are produced. The size must protect the fabric from snags and pulled threads during looping, seaming, stitching, inspection and the handling to which the fabric is subjected. It is also necessary that this sizing prevents the twist of the yarn from unravelling and that it sets the twist, particularly in the case of viscose threads having been twisted up to 40 turns.

A size for full fashioned hosiery knitted from yarns made from a cellulose base, must be very carefully balanced, if good running properties, good stitch formation and good general wear resistance are to be developed. Such asize must be readily removable by the usual boil-ofi methods.

Practical experience in factories and laboratories shows that one of the most serious drawbacks encounteredin the course of textile operations involving artificial yarns is the formation of electro-m'agnetie charges or so-called static upon the individual threads with the re sult that these threads repel each other and spread apart, resulting in what is commonly known as wild yarn, which impedes the treatment of the yarn to a very great extent.

It has been suggested that the treatment heretofore applied to conducting wires to'prevent static thereon, be extended to yarns; this treatment consists in the coating of wires with paraffin. However, this suggestion is unsatisfactory, since parafiin is not soluble in water, while a static-prevent coating should be capable of being boiled off in an aqueous solution prior to the dyeing of the yarn.

Therefore, another one of the principal objects of the present invention is the provision of knitting full fashioned hosiery and which is also a water-soluble static inhibitor for yarns, particularly yarns originating from. cellulose and used hosiery and for other purposes.

Yet another object is the provision of a coated or sized yarn originating from cellulose which is devoid of static and which is capable of being successfully subjected to various operations in- A volving rough treatment, including the knitting into full-fashioned hosiery.

Other objects of the present invention will become apparent in the course of the following specification.

In accomplishing the objects of the present invention it has now been found that a sizing or coating which after congealing, acts similarly to sizing containing mucilaginous matters, and is most suitable for the treatment of yarns having a cellulose base to be used in; knitting full-fashioned hosiery, and for eliminating static, can be prepared from oils, fats and waxes having a high melting point and a low iodine value.

These raw materials consist of partially natural or synthetic products or hydrogenated types mixed in such manner that the mixture has a melting point ranging between 40 C. and 70 C., and a maximum iodine value which should not exceed 30.

According to the present invention, 'a sizing may be made of mixtures of oils or fats which are emulsified or completely or partly saponified and which have a high melting point and a low iodine value. Since an oil or fat will have a high melting point and a low iodine value after having been hydrogenated, hydrogenated oils and fats will produce a most satisfactory sizing.

The high melting point governs the rapid congealing of the size and its filament-binding properties. Thus the melting point controls the hardness or softness of the sizing while the low iodine value reduces the absorption pf oxygen, thereby eliminating for all practical purposes the oxidation of the size and, in turn, reducing certain undesirable physical properties of the yarn, such as tenacity and elongation.

While the present invention includes the use of hydrogenated oils and fats, practical experionce has shown that, among others, the following fatty acids and wax-like substances were found to be most suitable:

Single pressed stearic acid having a melting point of 52 C. to 53 C. (determined by titer test) and an iodine value of 12 to 14.

Double pressed stearic acid having a melting point of 53 C. to 54 C. (titer test) and an iodine value of 8.

Triple pressed stearic acid having a melting point of 54 C. to 55 C. (titer test) and an iodine .value of 4 to 6.

Hydrogenated vegetable andanimal oils with melting points ranging between 50 C. and 65 C., congealing points and iodiine values up to 25 may be conveniently employed. Among them the following may be named:

Hydrogenated cotton seed oil having a melting point of 61 C. to 62 C. and an iodine value of 8 to 10.

Hydrogenated peanut oil having a melting point of 60 C. and an iodine value of 6 to 8.

Hydrogenated soya bean oil having a melting point of 61 C. and an iodine value of 25.

Hydrogenated sperm oil having a melting point 4 of 40 C. to 55 C. and an iodine value of 4 to 25.

Vegetable and animal glyceride. may be conveniently employed, including hydrogenated mixtures of glycerides having a melting point of 50 C. to 60 C. and an iodine value of 6 to 25.

Olive oil and tea seed oil were also found suitable. On the other hand, cocoanut oil has the disadvantage that it oxidizes rapidly,

Hydrogenated oils or similar products may be mixed with natural waxes in such manner as to obtain a good range of suitable melting points and iodine values.

All completely saponifiable waxes are suitable for this purpose, including the following: Spermaceti wax having a melting point of 40 C. to 50 C. and an iodine value of 2.5 to 4.

Japan wax having a melting point of .50 C. to 60 C. and an iodine value of 4 to 15.

It is also possible to use a series of incompletely saponifiable waxes, purified tallow, esters, etc., among them;

Candelilla wax having a melting point of F. to F. and an iodine' value of 14 to 36.

Carnauba wax having a melting point of to F. and an iodine value of 13.5.

Chinese wax having a melting point of 150 F. to 175 F. and an iodine value of 1.4 to 2.

'Bees wax having a melting point of 60 C. to 70 C. and an iodine value of 8 to 12, may also be used.

On the other hand, unsaponiflable hydrocarbons, such as paraffin, are unsuitable since they cannot be boiled ofi, thereby detrimentally affecting the dyeing.

The pliability of the sizing and of the yarn treated by the sizing are furthered by the addition of varying amounts of fatty 'acid soaps such as oleic acid and caustic soda and/or caustic potash.

These characteristics are developed to a fine degree by the addition of suitable lubricating and softening agents, including comparatively small amounts of various oils, such as mineral, vegetable, sulphonated, blown or partially saponified oils, emulsified and partially saponified fats, and oils modified in various degrees for the purpose of controlling the melting point and the pliability of the yarn. The lists of substances which may be satisfactorily utilized include any good grade sulphonated oils made from any suitable vegetable or mineral oils, sulphonated tallow or even good grades of peanut and olive oils, or diethanolamine or tri-ethanolamine soaps which assist in the penetration of the size into the yarn, due to their hygroscopic nature, and which have detergent properties, facilitating the subsequent removal of the sizing, These agents may be modified by saponification after sulphonation; they can be heated to remove excess amounts of water and can be neutralized or acidified. These softeners consisting of oils and soaps may be modifled in a well known manner by mixing them with each other to produce any desired result. It is apparent from the above that the method in accordance with the present invention includes the use of a size consisting of a solution of an esterifled higher fatty acid or an esterified higher fatty acid ester, an oil and a wax.

If greater pliability of the fat combination should be required, small amounts of known plasticizers can be added, such as ethylene glycol, diethylene glycol, glycerine, carbitol, etc.

The invention will appear more clearlyfrom the following examples which are given to illustrate preferred sizing compositions, but which are not to be considered as limitative of the present invention. The percentages set forth in the ex amples designate those by weight,

Eaample 1 Parts A mixture of hydrogenated soya, peanut and fish oils having a melting point of 55 C. to 60 C. and an iodine value of 20 to 25 "27.000 Stearic acid having a melting point of 53 C. to 54 C. (as titre) and an iodine value of 8 5.300 Oleic acid having a melting point of 8 C. 1

to 12 C. (as titre) and an iodine value of 88 1.500 Beeswax with a melting point of 68 C.

and an iodine value of 8 4.500 Caustic soda (NaOH) 0.850 Caustic potash (KOH) 0.125 A mixture of any suitable soluble vegetable and animal oils and dior triethanolamine soaps 4.500 A plasticizing agent, such as ethylene glycol, glycerine or diethylene glycol 1.000 -A preservative such as cresol or phenol compounds 0.500 Water 54.125

Example 2 Parts Hydrogenated cotton seed oil having a melting point of 61 C. to 62 C. and an iodine value of 8 27.000 Soap fiakes 6.000 Beeswax 4.500

Trioleate 4.000

Caustic soda 0.050 Diethyleneglycol 1.000 Water 58.000

Example 3 Parts Hydrogenated fish oil having a melting point of 45 C. to 48 C. and an iodine value of 25 to 30; 30.000 Stearic acid 5.000 Textile soap flakes 5.000 Beeswax 2.000 Japan wax 2.000 Triethanolamine 1.000 Water 55.000

Example 4 Parts A hydrogenated fat having a melting point of 60 C. to 63 C 10.500 Stearic acid 10.500 Beeswax 8.700 Oleic acid 3.333 Solid caustic soda 2.000 Water 65.000

A method of applying the size to the yarn, according to the present invention, comprises the use of a bath heated to 40 C. to 60 C. or to a higher temperature, if necessary, wherein each individual filament of the yarn is coated with a layer of a high-melting fat and all the filaments are firmly held together. The protective layers have excellent sizing properties and act like sericin upon natural silk, or paraflin upon wires. A sizing solution prepared in accordanc with the requirements of the present invention may contain as much as 80% or even 90% water, so that 100 pounds of dry yarn will contain after sizing but before drying, to pounds of water plus the weight of the sizing ingredients.

According to a preferred process of the present invention, the yam after being removed from the bath is extracted, shaken lightly and then placed upon drier rods where it is dried at temperatures of about 65 C. or higher. An advantage of the described sizes is that no capillary or wick action takes place during drying.

According to an important feature of the present invention, the yarn is scotched immediately after it has been dried and while it is still warm. At that time the yarn does not contain more than 4 or 5% of water and this amount is negligible for all practical purposes. Thus, since the scotching and straightening out of filaments is done after the yarn has been dried, this. small amount of water cannot affect the yarn adversely. Any sticking threads which are present prior to scotching will be separated easily by scotching the dry yarn.

Formerly, the scotching was carried out prior to drying while the yarn was in a wet state, This was found to be unsatisfactory with sizes containing a large percentage of water, and since, for instance, a 75 denier hose yarn will not stand a severe scotching treatment.

After drying, the yarn is humidified, twisted in the usual manner, and thereafter twist set and cooled.

The described new sizing compositions adhere well to the filaments and bind them together well; they produce a soft and pliable yarn, impart to the yarn good running properties on fullfashioned knitting machines, protect the full fashioned stocking fabric well from snags and runs, and are readily removable. Furthermore, the full-fashioned hose is free from distortion of stitch, perfect in form, and free from shiners. The danger of odor recrudescence in the size is considerably reduced and the danger of the appearance of acid-producing insoluble soaps is extremely small and negligible. The winding properties of the yarn are very good and the stability of the treated yarns is outstanding.

Various commercial boil-01f compounds may be used in a customary manner for the removal of the size, whereupon perfect level dying is attained. In fact, excessively high amounts of boil-oil baths could be eliminated. No special precautions are necessary in the removal of the size and the dyeing procedure requires no changes.

- A most important characteristic feature of any yarns coated by any sizes made in accordance with the present invention, is that such yarns will be devoid of so-called static, or static electricity creating electro-magnetic forces which cause the individual threads of a bundle to repel each other and to fiare outwardly. As already stated, the wildness" of such yarns is a most serious drawback, since it impedes the proper treatment of the yarns and exposes the yarns to tangling and breakage.

The size prepared in accordance with the present invention covers fully the filaments of the yarn and acts as an insulating layer which prevents the accumulation of static electricity charges upon the filaments of the yarn. Therefore, the described preparations may be used not only as a size, but independently thereof as a static inhibitor upon any types of yarns whenever it is necessary to provide yarns which are devoid of static.

according to the present invention have been sucamass? cessfully applied to yarns of cellulose base, particularly viscose yarns of 50 to 75 denier, and also to various other yarns, including cotton.

It is apparent that the described articles, compositions and methods are subject to wide variations and modifications without departing from the scope or intent of the present invention, all of which variations and modifications are to be included within the scope of the present invention. The term "scotchlng, as used throughout the specification and claim, describes a process consisting of the beating of the yarn for the purpose of breaking up slugs and aligning the threads. Heretofore, it was impossible to carry out the scotching when the yarn is dried while the process of the present invention makesit possible to carry out the scotching while the yarn is dried and still warm. What is claimed is:

A method of treating synthetic yarns in the production of sheer knit goods, said method comprising, in combination, sizing the yarn at a bath heated to not less than 40 C. with a self-emulsiflabie mixture of a hydrogenated oil, a solid fatty acid and a soap, said mixture-having a melting point of 40 C. to 70 C. and an iodine value not exceeding 30, drying the sized yarn at a temperature of at least 50 C., reducing its water contents to about 4 to 5% and immediately thereafter scotching the yarn while it is in a dry and still warm state, thereby aligning the threads and eliminating harshness as well as static;

HERBERT FREUND.

Number Name Date 2,067,888 Chamberlin Jan. 19, 1937 2,010,900 Schneider Aug, 13, 1935 2,005,785 Hibbert June 25, 1935 1,725,829 Ryley Aug. 27, 1929 1,637,475 Davis Aug. 2, 1927 1,423,041 Snyder July 18, 1922 2,027,390 Lazier Jan. 14, 1936 2,308,355 Colbeth Jan, 12, 1943 2,127,586 Dreyfus Aug. 23, 1938 1,872,913 Dreyfus Aug. 23, 1932 2,205,042 Lenher June 18, 1940 2,067,947 Platt Jan. 19, 1937- 1,819,241 Hirschberger Aug. 18, 1931v 2,340,051 Goodings Jan. 15, 1944 2,011,632 Harris Aug. 20, 1935 2,297,135 Davis et al. Sept. 29, 1942 Re. 20,417 Hood -L June 22, 1937 1,681,745 Pohl Aug, 21, 1928 20,925 Richardson July 13, 1858 87,005 Semple et al. Feb. 16, 1869 1,728,682 Kampf Sept. 29, 1929 1,276,507 Ellis Aug. 20, 1918 FOREIGN PATENTS Number Country Date 381,764 British Oct, 13, 1932 388,769

nnmnnncss ormn The following references are of record in the file of this patent: Y

UNITED STATES PATENTS British Mar. 1, 1933 

